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1.
BMC Geriatr ; 24(1): 131, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38373895

RESUMO

BACKGROUND: As stroke has become the leading cause of death and disability in China, it has induced a heavy disease burden on society, families, and patients. Despite much attention within the literature, the effect of multiple risk factors on length of stay (LOS) and inpatient costs in China is still not fully understood. AIM: To analyse the association between the number of risk factors combined and inpatient costs among adults with stroke and explore the mediating effect of LOS on inpatient costs. METHODS: A retrospective cross-sectional study was conducted among stroke patients in a tertiary hospital in Nantong City from January 2018 to December 2019. Lifestyle factors (smoking status, exercise), personal disease history (overweight, hypertension, dyslipidemia, diabetes mellitus, atrial fibrillation), family history of stroke, and demographic characteristics were interviewed by trained nurses. Inpatient costs and LOS were extracted from electronic medical records. Hierarchical multiple linear regression models and mediation analysis were used to examine the direct and indirect effects of the number of risk factors combined for stroke on inpatient costs. RESULTS: A total of 620 individuals were included, comprising 391 ischaemic stroke patients and 229 haemorrhagic stroke patients, and the mean age was 63.2 years, with 60.32% being male. The overall mean cost for stroke inpatients was 30730.78 CNY ($ 4444.91), and the average length of stay (LOS) was 12.50 days. Mediation analysis indicated that the greater number of risk factors was not only directly related to higher inpatient costs (direct effect = 0.16, 95%CI:[0.11,0.22]), but also indirectly associated with inpatient cost through longer LOS (indirect effect = 0.08, 95% CI: [0.04,0.11]). Furthermore, patients with high risk of stroke had longer LOS than those in low-risk patients, which in turn led to heavier hospitalization expenses. CONCLUSIONS: Both the greater number of risk factors and high-risk rating among stroke patients increased the length of stay and inpatient costs. Preventing and controlling risk behaviors of stroke should be strengthened.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Humanos , Masculino , Feminino , Tempo de Internação , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/terapia , Pacientes Internados , Estudos Retrospectivos , Estudos Transversais , Hospitalização , Fatores de Risco , China/epidemiologia , Custos Hospitalares
2.
BMC Public Health ; 24(1): 1035, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38614987

RESUMO

INTRODUCTION: Widespread concern exists in today's world regarding self-harm and interpersonal violence. This study to analyze the changes in temporal trends and spatial patterns of risk factors and burdens of self-harm and interpersonal violence using the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. METHODS: Temporal trends in self-harm and interpersonal violence were initially summarized using the estimated annual percentage change (EAPC). Data were compiled and visualized to delineate changes in disease burden and factors influencing self-harm and interpersonal violence from 1990 to 2019, stratified by gender, age and GBD region. RESULTS: In 2019, the DALY rates of self-harm were 424.7(95% UI 383.25, 466.93). Over the period from 1999 to 2019, self-harm exhibited an overall decreasing trend, with the EAPC of -1.5351 (95% CI -1.6194, -1.4507), -2.0205 (95% CI -2.166, -1.8740) and -2.0605 (95% CI -2.2089, -1.9119), respectively. In contrast, the incidence rate of interpersonal violence was significantly higher than self-harm, with a rate of 413.44 (95% UI 329.88, 502.37) per 100,000 population. Mortality and DALYs of interpersonal violence were lower than those of self-harm, at 5.22 (95% UI 4.87, 5.63) and 342.43 (95% UI 316.61, 371.55). Disease burden of self-harm and interpersonal violence varied by gender, age groups and region. Specific risk factors showed that alcohol use, high temperature and drug use were the main risk factors for self-harm, while alcohol use, intimate partner violence and high temperature were associated with interpersonal violence. Low temperature was a common protective factor for both self-harm and interpersonal violence. The burden of self-harm and interpersonal violence was attributed to different factors influences in different SDI regions. CONCLUSIONS: The study explored temporal trends and spatial distribution of the global disease burden of self-harm and interpersonal violence, emphasizing the significant impact of factors such as alcohol use, temperature, and drug use on disease burden. Further research and policy actions are needed to interpret recent changes of disease burden of self-harm and interpersonal violence, and dedicated efforts should be implemented to devise evidence-based interventions and policies to curtail risk factors and protect high-risk groups.


Assuntos
Violência por Parceiro Íntimo , Comportamento Autodestrutivo , Humanos , Carga Global da Doença , Comportamento Autodestrutivo/epidemiologia , Consumo de Bebidas Alcoólicas , Fatores de Risco
3.
Plant Physiol ; 188(4): 1852-1865, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35088863

RESUMO

Site-specific gene stacking could reduce the number of segregating loci and expedite the introgression of transgenes from experimental lines to field lines. Recombinase-mediated site-specific gene stacking provides a flexible and efficient solution, but this approach requires a recombinase recognition site in the genome. Here, we describe several cotton (Gossypium hirsutum cv. Coker 312) target lines suitable for Mycobacteriophage Bxb1 recombinase-mediated gene stacking. Obtained through the empirical screening of random insertion events, each of these target lines contains a single intact copy of the target construct with precise sequences of RS2, lox, and attP sites that is not inserted within or close to a known gene or near a centromere and shows good expression of the reporter gene gfp. Gene stacking was tested with insertion of different combinations of three candidate genes for resistance to verticillium wilt into three cotton target lines: CTS1, CTS3, and CTS4. Nine site-specific integration events were recovered from 95 independently transformed embryogenic calluses. Southern and DNA sequence analyses of regenerated plants confirmed precise site-specific integration, and resistance to verticillium wilt was observed for plant CTS1i3, which has a single precise copy of site-specifically integrated DNA. These cotton target lines can serve as foundation lines for recombinase-mediated gene stacking to facilitate precise DNA integration and introgression to field cultivars.


Assuntos
Gossypium , Verticillium , Resistência à Doença/genética , Gossypium/genética , Gossypium/metabolismo , Doenças das Plantas/genética , Plantas Geneticamente Modificadas/metabolismo , Recombinases/genética , Recombinases/metabolismo , Transgenes
4.
BMC Psychiatry ; 23(1): 497, 2023 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-37434160

RESUMO

BACKGROUND: Long working hours and effort-reward imbalance (ERI) among medical workers may contribute to poor mental health and reduced productivity. However, the potential mechanisms among them are not well understood. This study aimed to explore the role of depressive symptoms and ERI in the relationship between long working hours and presenteeism among village doctors. METHODS: We conducted a cross-sectional study in Jiangsu Province, eastern China. 705 village doctors were assessed for working hours, ERI (the Effort-Reward Imbalance Questionnaire, ERI questionnaire), presenteeism (6-item Stanford Presenteeism Scale, SPS-6 Scale), and depressive symptoms (12-item General Health Questionnaire, GHQ-12). A moderated mediation model was used to test the role of depressive symptoms (M), and ERI (W) in the relationship between long working hours (X) and presenteeism (Y). RESULTS: 45.11% of the village doctors worked more than 55 h per week, and 55.89% were exposed to ERI. The prevalence of depressive symptoms among Chinese village doctors was 40.85%. Long working hours (≥ 55 h per week) were significantly associated with presenteeism behaviors (ß = 2.17, P < 0.001). Mediation analysis demonstrated that depressive symptoms (GHQ score > 3) could partly mediate the relationship between long working hours and presenteeism (indirect effect ß = 0.64, P < 0.001). Moderated mediation further indicated that the interaction of long working hours and ERI was significantly and positively associated with depressive symptoms, which in turn predicted elevated presenteeism behaviors. CONCLUSIONS: Depressive symptoms had a mediating role in the association of long working hours with presenteeism behaviors among Chinese village doctors and ERI augment their negative effects.


Assuntos
Depressão , Médicos , Presenteísmo , Recompensa , Humanos , Estudos Transversais , Depressão/epidemiologia , População do Leste Asiático , Médicos/psicologia
5.
Wei Sheng Yan Jiu ; 52(2): 226-231, 2023 Mar.
Artigo em Zh | MEDLINE | ID: mdl-37062684

RESUMO

OBJECTIVE: To analyze the epidemiological characteristics of foodborne disease outbreaks in China and to provide references for formulating prevention strategies of foodborne diseases in China. METHODS: Collect the monitoring data reported in China's foodborne disease outbreak monitoring system from 2011 to 2020, and calculate relevant indicators. RESULTS: During 2011 and 2020 in 30 provinces(autonomous region, municipality), a total of 35 806 foodborne disease outbreaks were reported, which caused 266 968 illnesses. The western region had the largest number of reported incidents and the largest number of patients, Yunnan Province had the largest percentage of outbreaks(17.7%) and the largest percentage of cases(15.81%). Poisonous mushrooms and microorganisms are the main pathogenic factors. Poisonous mushrooms caused the largest percentage of foodborne disease outbreaks, accounting for 29.09% of the total. Microorganisms caused the largest percentage of cases, accounting for 35.69% of the total. Salmonella and Vibrio parahaemolyticus are the main pathogens. Catering service units were the main places of foodborne disease outbreaks, responsible for the largest percentage of outbreaks(49.31%) and cases(70.59%). CONCLUSION: From 2011 to 2020, the number of reported incidents and the number of patients in foodborne disease outbreaks in China showed an upward trend.


Assuntos
Doenças Transmitidas por Alimentos , Humanos , China/epidemiologia , Doenças Transmitidas por Alimentos/epidemiologia , Surtos de Doenças
6.
Theor Appl Genet ; 135(7): 2333-2340, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35596798

RESUMO

KEY MESSAGE: N-cre and C-cre added in separate lines reassemble functional Cre in F1 progeny to excise unnecessary DNA, including cre DNA, thereby eliminating generations needed to cross in and out cre. Crop improvement via transgenesis can benefit through efficient DNA integration strategies. As new traits are developed, new transgenes can be stacked by in planta site-specific integration near previous transgenes, thereby facilitating their introgression to field cultivars as a single segregation locus. However, as each round of integration often requires use of selectable markers, it is more convenient to reuse the selection scheme. The Cre recombinase can be used to delete away previously used selection genes, and other DNA no longer needed after transformation, but the constitutive production of this DNA scanning protein can also affect plant growth. We had previously described in Arabidopsis a split Cre protein fragment complement scheme to reassemble a functional Cre recombinase. As our goal for developing this system was to deploy its use in major crop plants, here we show that Cre protein fragment complementation works in rice with precise recombination structures confirmed by DNA sequencing. As each N-terminal and C-terminal fragment is also flanked by lox recombination sites, they can also self-excise to avoid the need to segregate away the cre DNA. Options to form F1 hybrids homozygous for one transgene, or hemizygous for two different transgenes at the same chromosome location, are discussed.


Assuntos
Arabidopsis , Oryza , Arabidopsis/genética , DNA , Integrases , Oryza/genética , Plantas Geneticamente Modificadas/genética , Recombinação Genética , Transgenes
7.
Theor Appl Genet ; 135(4): 1163-1175, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35325256

RESUMO

KEY MESSAGE: Five soybean target lines with recombinase sites at suitable genomic positions were obtained and tested for site-specific gene stacking. For introgression of new transgenic traits to field cultivars, adding new DNA to an existing transgene locus would reduce the number of segregating loci to reassemble back into a breeding line. We described previously an in planta transgene stacking system using the Bxb1 integrase to direct new DNA into a genomic target, but for this system to operate, the target locus must have a preexisting recombination site for Bxb1-mediated integration. Here, we describe 5 soybean target lines from the screening of 118 Agrobacterium-mediated transgenic plants that were positive for gus expression. Each of the 5 target lines has a single copy of the transgenic DNA with precise DNA sequences of the recombinase recognition sites, located at least 1 kb away from the nearest coding region, not close to the centromere, and showed good expression of the reporter gene. We tested Bxb1 integrase-mediated integration of a gfp-containing plasmid into each of these lines and showed precise site-specific integration in bombarded calluses. For plant regeneration, we used embryonic axes of mature soybean seeds to conduct a new set of biolistic transformation with a DsRed-containing plasmid. Three integration events were regenerated into whole plants, demonstrating the principle that target lines can serve as foundation lines for the stacking of DNA to predefined locations in the soybean genome.


Assuntos
Glycine max , Recombinases , Integrases/genética , Integrases/metabolismo , Melhoramento Vegetal , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Recombinases/genética , Recombinases/metabolismo , Glycine max/genética , Glycine max/metabolismo , Transgenes
8.
Int J Mol Sci ; 23(16)2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-36012650

RESUMO

The clustering of transgenes at a chromosome location minimizes the number of segregating loci that needs to be introgressed to field cultivars. Transgenes could be efficiently stacked through site-specific recombination and a recombinase-mediated in planta gene stacking process was described previously in tobacco based on the Mycobacteriophage Bxb1 site-specific integration system. Since this process requires a recombination site in the genome, this work describes the generation of target sites in the Japonica rice genome. Agrobacterium-mediated gene transfer yielded ~4000 random-insertion lines. Seven lines met the criteria of being single copy, not close to a centromere, not inserted within or close to a known gene or repetitive DNA, having precise recombination site sequences on both ends, and able to express the reporter gene. Each target line tested was able to accept the site-specific integration of a new gfp-containing plasmid and in three of those lines, we regenerated fertile plants. These target lines could be used as foundation lines for stacking new traits into Japonica rice.


Assuntos
Oryza , Integrases/genética , Oryza/genética , Plantas Geneticamente Modificadas/genética , Recombinases/genética , Recombinação Genética , Nicotiana/genética , Transgenes
9.
Chaos ; 29(4): 043128, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31042935

RESUMO

Most research suggests that humans can optimize their behavior by imitating other humans. However, it remains unclear whether humans actually imitate others in real-life situations. To address this question, we conducted spatial public goods experiments with voluntary participation. In direct contrast to the prevailing view, the results of our experiments show that imitation plays an insignificant role in the decision making process. Furthermore, we found that the nature of human decision making relied more on their performances in the game's earlier history rather than the performance they observed in others. The action that gained better results in one's own history had a higher chance to be adopted even if this action did not work for the others.


Assuntos
Tomada de Decisões , Teoria dos Jogos , Comportamento Imitativo , Feminino , Humanos , Masculino
10.
Proteomics ; 17(9)2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28225203

RESUMO

WD-40 repeat-containing protein MSI4 (FVE)/MSI4 plays important roles in determining flowering time in Arabidopsis. However, its function is unexplored in wheat. In the present study, coimmunoprecipitation and nanoscale liquid chromatography coupled to MS/MS were used to identify FVE in wheat (TaFVE)-interacting or associated proteins. Altogether 89 differentially expressed proteins showed the same downregulated expression trends as TaFVE in wheat line 5660M. Among them, 62 proteins were further predicted to be involved in the interaction network of TaFVE and 11 proteins have been shown to be potential TaFVE interactors based on curated databases and experimentally determined in other species by the STRING. Both yeast two-hybrid assay and bimolecular fluorescence complementation assay showed that histone deacetylase 6 and histone deacetylase 15 directly interacted with TaFVE. Multiple chromatin-remodelling proteins and polycomb group proteins were also identified and predicted to interact with TaFVE. These results showed that TaFVE directly interacted with multiple proteins to form multiple complexes to regulate spike developmental process, e.g. histone deacetylate, chromatin-remodelling and polycomb repressive complex 2 complexes. In addition, multiple flower development regulation factors (e.g. flowering locus K homology domain, flowering time control protein FPA, FY, flowering time control protein FCA, APETALA 1) involved in floral transition were also identified in the present study. Taken together, these results further elucidate the regulatory functions of TaFVE and help reveal the genetic mechanisms underlying wheat spike differentiation.


Assuntos
Flores/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Mapas de Interação de Proteínas , Proteômica/métodos , Triticum/crescimento & desenvolvimento , Triticum/metabolismo , Bioensaio , Cromatografia Líquida , Bases de Dados de Proteínas , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Espectrometria de Massas em Tandem , Triticum/genética
13.
Environ Microbiol Rep ; 16(2): e13256, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38575150

RESUMO

This study examined the effects of three Bacillus strains and one Saccharomyces cerevisiae strain on nitrogen transformation and microbial communities in pig and chicken manure compost. The findings revealed that the use of compound microbial inoculants increased the compost temperature, accelerated moisture reduction, enhanced cellulase activity, and stimulated the accumulation of NH4 +-N, NO3 --N, and total nitrogen (TN), resulting in a 9% increase in TN content. The abundance of Firmicutes decreased by 3.95% at the maturation phase, while Actinobacteria and Bacteroidetes increased by 1.64% and 1.85%, respectively. Inoculation led to an increase in amoA, nxrA and nifH gene copy numbers, while simultaneously reducing the abundance of nirK, nosZ and nirS genes. It also resulted in an increase in functional enzyme levels, specifically nif and amo, with a corresponding decrease in nor. Clostridium, Phascolarctobacterium, Eubacterium and Faecalibacterium from the class Clostridium, which have a significant correlation with nifH and nxrA genes, suggest their likely crucial role in nitrogen retention and fixation. Inoculation aided in the removal of pathogenic bacteria and antibiotic resistance genes (ARGs) like fluoroquinolones, nucleosides and nitroimidazole. This study provides effective theoretical support for the mechanism of nitrogen retention and fixation, and for improving the quality of compost.


Assuntos
Compostagem , Microbiota , Animais , Suínos , Esterco , Gado , Nitrogênio , Solo , Bactérias/genética , Microbiota/genética
14.
Talanta ; 270: 125557, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38128284

RESUMO

As the development of global population and industry civilization, the accurate and sensitive detection of intended analytes is becoming an important and great challenge in the field of environmental, medical, and public safety. Recently, electrochemical biosensors have been constructed and used in sensing fields, such as antibiotics, pesticides, specific markers of cancer, and so on. Functional materials have been designed and prepared to enhance detection performance. Among all reported materials, covalent organic frameworks (COFs) are emerging as porous crystalline materials to construct electrochemical biosensors, because COFs have many unique advantages, including large surface area, high stability, atom-level designability, and diversity, to achieve a far better sensing performance. In this comprehensive review, we not only summarize state-of-the-art electrochemical biosensors based on COFs and their hybrid materials but also highlight and discuss some typical examples in detail. We finally provide the challenge and future perspective of COFs-based electrochemical biosensors.

15.
Int J Biol Macromol ; 264(Pt 2): 130673, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38458290

RESUMO

Noble metal nanoparticles show good application prospects in biosensors and anti-tumor drug research. Herein, the near-spherical silver­palladium bimetallic nanoparticles supported by elm pod polysaccharide (EPP-AgPd1.5 NPs) were prepared by using the elm pod polysaccharide (EPP). EPP acts as a stabilizer and reducing agent due to its water solubility and weak reducing ability. The particle size of EPP-AgPd1.5 NPs was 33.6 ± 5.5 nm. In addition, EPP-AgPd1.5 NPs had peroxidase-like activity to catalyze 3,3',5,5'-tetramethylbenzidine (TMB) to oxidized TMB by catalyzing H2O2 to OH. Based on the peroxidase-like activity of EPP-AgPd1.5 NPs, a method for detecting glutathione was established, and the detection limit and linear range of glutathione concentration were 0.279 µM and 0-400 µM, respectively. More importantly, the photothermal conversion efficiency of EPP-AgPd1.5 NPs reached 39.7 %, and their inhibition rate in HeLa cells reached 69.9 %. Silver­palladium bimetallic nanoparticles stabilized by EPP had good performance in glutathione detection and anti-tumor drugs.


Assuntos
Nanopartículas Metálicas , Peroxidase , Humanos , Prata , Paládio , Peróxido de Hidrogênio , Células HeLa , Polissacarídeos/farmacologia , Glutationa , Colorimetria/métodos
16.
BMC Psychol ; 12(1): 341, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858753

RESUMO

BACKGROUND: Social media addiction (SMA) is an increasing problem, especially among young adults. Little is known about university students' SMA and family functioning. This study aimed to explore the mediating effect of depressive symptoms and the moderating effect of peer support in the relationship between family functioning and SMA among young adults. METHODS: A sample of 1862 Chinese university students completed an online survey including the Bergen Social Media Addiction Scale (BSMAS), Family APGAR, the Patient Health Questionnaire (PHQ-9), peer support, and demographic characteristics. Hierarchical regression and moderated mediation analysis were used to test the effects and pathways among them. RESULTS: Of the 1840 participants, 30.11% experienced SMA, 38.80% had family dysfunction and 15.98% had depressive symptoms. Hierarchical multiple regression showed better family functioning significantly predicted less SMA (ß = -0.26, p < 0.001) and lower depressive symptoms (ß = -0.58, p < 0.001), after adjusting for covariates. Mediation analysis verified that depressive symptoms mediated the effect of family functioning on SMA (indirect effect = -0.22, 95%CI[-0.28, -0.17]). Furthermore, the interaction of family functioning and peer support was negatively related to depressive symptoms (ß= -0.03, 95% CI[-0.05, -0.01]) and the interaction of depressive symptoms and peer support was positively related to SMA (ß = 0.01, 95%CI[0.004, 0.02]). Additional analysis further confirmed that peer support decreased depressive symptoms among young adults from dysfunctional families, and increased SMA behaviors in individuals with depressive symptoms. CONCLUSION: Better family functioning and lower depressive symptoms may contribute to less social media addiction among Chinese university students. Peer support could moderate the mediating role of depressive symptoms on social media addiction in individuals with family dysfunction.


Assuntos
Depressão , Grupo Associado , Apoio Social , Estudantes , Humanos , Masculino , Feminino , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Depressão/psicologia , Depressão/epidemiologia , Adulto Jovem , Universidades , Adulto , Mídias Sociais/estatística & dados numéricos , Transtorno de Adição à Internet/psicologia , China , Adolescente , Inquéritos e Questionários , Relações Familiares/psicologia , Família/psicologia , Análise de Mediação
17.
Dalton Trans ; 52(33): 11552-11557, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37545403

RESUMO

Functional materials are considered one of the most critical factors in constructing high-performance electrochemical aptasensors in the sensing field. In this work, the microporous Zr-MOF UiO-66 (UiO = Universitetet i Oslo) is selected for assembly with carbon nanotubes (CNTs) to prepare a CNT@UiO-66 composite. The as-synthesized CNT@UiO-66 composite has a high surface area, excellent stability, good electrical conductivity, and abundant Zr(IV) sites, conferring it great potential for application in fabricating high-performance electrochemical aptasensors. It is gratifying that this electrochemical impedimetric aptasensor can detect trace oxytetracycline (OTC) from 0.01 to 0.7 pg mL-1 with a low limit of detection (LOD) of 1.48 fg mL-1. Meanwhile, this fabricated sensor based on CNT@UiO-66 has fine stability, excellent selectivity, and available reproducibility. In particular, the CNT@UiO-66-based aptasensor can quantitatively detect the OTC concentration in real samples.

18.
Int J Biol Macromol ; 233: 123513, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36739057

RESUMO

The development of nanozymes using noble metal nanoparticles to replace natural peroxidase in bio-related detection has been gain great interest. Noble metal nanoparticles with small size have large specific surface area. However, small noble metal nanoparticles tend to aggregate without stabilizer. In this paper, small Pd nanoparticles (3-6 nm) stabilized by bitter gourd polysaccharide (Pdn-BGP NPs) were prepared by using bitter gourd polysaccharide as reducing agent and stabilizing agent. Pd25-BGP NPs had peroxidase-like catalytic property. And the catalytic kinetics of Pd25-BGP NPs towards substrates conformed to the Michaelis-Menten equation. Furthermore, a method was established to detect H2O2 using Pd25-BGP NPs. The linear range and detection limit of this method was 20-320 µM and 2.04 µM, respectively. Finally, Pd25-BGP NPs had good biocompatibility when the concentration was less than 80 µg/mL. The prepared Pd nanoparticles with high stability showed their good prospect in H2O2 detection.


Assuntos
Nanopartículas Metálicas , Momordica charantia , Peroxidase/química , Peróxido de Hidrogênio/química , Nanopartículas Metálicas/química , Polissacarídeos/química , Corantes/química , Colorimetria/métodos
19.
Polymers (Basel) ; 15(14)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37514537

RESUMO

Hydroquinone poses a major threat to human health and is refractory to degradation, so it is important to establish a convenient detection method. In this paper, we present a novel colorimetric method for the detection of hydroquinone based on a peroxidase-like Pd nanozyme. The vancomycin-stabilized palladium nanoparticles (Van-Pdn NPs, n = 0.5, 1, 2) were prepared using vancomycin as a biological template. The successful synthesis of Van-Pdn NPs (n = 0.5, 1, 2) was demonstrated by UV-vis spectrophotometry, transmission electron microscopy, and X-ray diffraction. The sizes of Pd nanoparticles inside Van-Pd0.5 NPs, Van-Pd1 NPs, and Van-Pd2 NPs were 2.6 ± 0.5 nm, 2.9 ± 0.6 nm, and 4.3 ± 0.5 nm, respectively. Furthermore, Van-Pd2 NPs exhibited excellent biocompatibility based on the MTT assay. More importantly, Van-Pd2 NPs had good peroxidase-like activity. A reliable hydroquinone detection method was established based on the peroxidase-like activity of Van-Pd2 NPs, and the detection limit was as low as 0.323 µM. Therefore, vancomycin improved the peroxidase-like activity and biocompatibility of Van-Pd2 NPs. Van-Pd2 NPs have good application prospects in the colorimetric detection of hydroquinone.

20.
Int J Biol Macromol ; 253(Pt 1): 126552, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37660849

RESUMO

Organophosphorus pesticides can inhibit the activity of acetylcholinesterase and cause neurological diseases. Therefore, it is crucial to establish an efficient and sensitive platform for organophosphorus pesticide detection. In this work, we extracted aloe polysaccharide (AP) from aloe vera with the number average molecular weight of 27760 Da and investigated its reducing property. We prepared aloe polysaccharide stabilized platinum nanoflowers (AP-Ptn NFs), their particle size ranges were 29.4-67.3 nm. Furthermore, AP-Ptn NFs exhibited excellent oxidase-like activity and the catalytic kinetics followed the typical Michaelis-Menten equation. They showed strong affinity for 3,3',5,5'-tetramethylbenzidine substrates. More importantly, we developed a simple and effective strategy for the sensitive colorimetric detection of organophosphorus pesticides in food using biocompatible AP-Ptn NFs. The detection range was 0.5 µg/L - 140 mg/L, which was wider than many previously reported nanozyme detection systems. This colorimetric biosensor had good selectivity and good promise for bioassay analysis.


Assuntos
Aloe , Técnicas Biossensoriais , Praguicidas , Praguicidas/análise , Compostos Organofosforados/análise , Acetilcolinesterase/química , Platina , Aloe/química , Colorimetria , Polissacarídeos/química
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